Influence of the Thiazole Backbone on the Structural, Redox, and Optical Properties of Dithiolene and Diselenolene Complexes

Metalation of N-methyl-1,3-thiazoline-2-thione followed by reaction with elemental S or Se affords a simple and
efficient approach to N-methyl-1,3-thiazoline-2-thione-4,5-dithiolate (Me-thiazdt) and the diselenolate (Me-thiazds)
analogue. In the presence of metal II centers such as Zn, Ni, and Pd these ligands afford the corresponding
dianionic dithiolene and diselenolene complexes. The Ni and Pd dianionic complexes are easily oxidized into the
monoanionic species. Complexes were isolated and characterized by single-crystal X-ray crystallography. Most
often a substitutional S/N−Me disorder is observed, attributable to the square-planar trans complexes disordered
on two positions or coexistence of both cis and trans isomers on inversion centers. Monoanionic complexes exhibit
a strong NIR absorption band with ε values up to 33 750 M-1 cm-1.